import i18n from "i18next";
import { initReactI18next } from "react-i18next";
import moment from "moment";
import en from "./en";
import dk from "./dk";

i18n
  .use(initReactI18next) // passes i18n down to react-i18next
  .init({
    resources: {
      en,
      dk
    },
    lng: "en",
    fallbackLng: "en",
    keySeparator: false, // we do not use keys in form messages.welcome

    interpolation: {
      escapeValue: false, // react already safes from xss
      // parse format string, it should match the following pattern
      // {{value, formatter, key1 = value1, key2 = value2, keyN = valueN}}
      format(value, format, lng) {
        const parts = format.split(",");
        const formatterName = parts.shift();
        const params = parts
          .map(x => x.split("=").map(y => y.trim()))
          .reduce((obj, pair) => {
            if (pair.length > 1) {
              obj[pair[0]] = pair[1];
            } else {
              obj[pair[0]] = pair[0];
            }
            return obj;
          }, {});
        const formatter = formatters[formatterName];
        if (formatter) {
          return formatter(value, params, parts.join(","), lng);
        }
        return value;
      }
    }
  });

export default i18n;

const formatters = {
  /**
   * date formatter
   * @param value
   * @param params
   * @param format
   * @return {string}
   */
  date(value, params, format) {
    switch (value) {
      case "now":
        value = moment();
        break;
      case "yesterday":
        value = moment().add(-1, "d");
        break;
      case "tomorrow":
        value = moment().add(1, "d");
        break;
    }
    return moment(value).format(format);
  },
  /**
   * amount formatter
   * @param value
   * @param zero
   * @param many
   * @param others
   * @return {string}
   */
  amount(value, { zero, many, others }) {
    if (!value && zero) return i18n.t(zero);
    if (value > 1 && many) return i18n.t(many, { value });
    return i18n.t(others, { value });
  },
  /**
   * list formatter
   * @param list    list of string
   * @param empty   indicate the text to display if no item
   * @param others  indicate the text to display for the rest of items
   * @param x       indicate first items should be display (default = 1)
   * @param sep     indicate list item separator (default = comma)
   * @return {string|string | *|*}
   *
   * Samples:
   * users = ['user1', 'user2', 'user3']
   * {{users, list, empty=noUser, others=otherUsers, x=2}}
   * noUser: No user
   * otherUsers: and {{count}} other(s)
   * output: user1, user2 and 1 other(s)
   */
  list(list, { empty, others, x = 1, sep = "," }) {
    // show empty text if list is empty
    if (!list || !list.length) return i18n.t(empty);
    // show first item value if list has only one item
    if (list.length === 1) return list[0];
    // show first x item values if list has more than x items
    return (
      list.slice(0, x).join(sep) + i18n.t(others, { count: list.length - 1 })
    );
  }
};